Small parts of the Upper Lahn Valley in the northwest belong, together with the town of Bad Laasphe, also to the district of Siegen-Wittgenstein, North Rhine-Westphalia.

The Gladenbach Highlands is largely coextensive with the Lahn-Dill Uplands Nature Park which extends further west, however, but is somewhat less extensive in the southeast and whose boundaries tend to line up with those of the sponsoring municipalities.

In addition, not insignificant areas belong to the historical Hessian Hinterland, which is why the two named articles refer to one another, as far as regional associations, culture and history are concerned.

Geology and mining will be largely covered in the article on the Lahn-Dill Region On the rivers Lahn and Dill the following towns - clockwise from the north - border the Gladenbach Uplands: The northwest transitions to the Rothaar Mountains are comparatively fluid.

The natural regions mentioned above are generally divided between the catchment areas of the der Lahn and Dill tributaries and the landscapes separated by these rivers.